JPS6027354B2 - Ground drilling equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The purpose of the present invention is to dig a pile hole for foundation preparation, etc., and at the same time strongly consolidate the surrounding wall of the hole so that the pile construction work can proceed smoothly and reliably. It is related to the device.

Conventionally, earth augers, so-called ground drilling devices, which have various types of pre-drilling blades attached to their tips have been used during foundation preparation work such as ground improvement construction, but these ground drilling devices excavate the ground. Because of this, it is inevitable that the surrounding wall of the borehole will collapse during or after the borehole excavation, which will seriously impede subsequent work.

In order to prevent such concerns, a device that strengthens the peripheral wall of the hole by pounding or pressing it from the inside is usually used during or after drilling the pile hole. However, this device has the disadvantage that it has a complicated structure and requires considerable skill in handling, and it is difficult to solidify the peripheral wall of the hole with complete certainty.

The present invention focuses on the above-mentioned drawbacks and improves the shape of the conventional auger tip drilling blade, thereby providing a new ground drilling device that is capable of extremely powerfully and reliably crushing the surrounding wall of the trench at the same time as digging. A conical tip portion is provided at the tip of the shaft, and an expansion piece is attached with each apex angle green of the conical tip portion as a base and has a cutting edge length that is longer than the rotational circumference of the auger outer diameter in the non-rotating direction. It is an object of the present invention to provide a ground drilling device characterized by the following.

Embodiments of the present invention will be explained in detail below with reference to the drawings illustrating the embodiments. 1 is an auger shaft having a rectangular cross-section and a substantially triangular shape, and has a triangular cone-shaped conical end fitting 2 at its tip end; Drill tip fitting 2
As shown in the illustrated example, substantially triangular expansion pieces 3 are provided integrally extending in the non-rotation direction on each apex edge 2', and each expansion piece 3
A pressed earth surface is formed by bending the blade surface in the axial direction.

The tip of the triangular expansion piece 3 has a blade length with a rotation locus b that is larger than the outer diameter of the auger shaft 1, that is, the rotational circumference a, and the bottom of the expansion piece 3 is Ayabe has 4 blades each...
is attached.

Further, each column surface 1' of the auger shaft 1 is curved inward toward Wakkanai to form a pressed earth surface, and inside the shaft there is an injection port 5 that opens at the tip of the auger tip fitting 2, and water suitable for pouring water. A flow pipe 6 such as mortar is arranged.

The drilling device according to the present invention has the above-mentioned configuration. Next, to explain its operating state, the auger shaft 1 is connected to the drive machine 7 and lowered into a predetermined ground, and the drive machine 7 When driven, the tip metal fitting 2 rotates, and the tip digging blade 4 digs into the ground to make the hole A.

As a result, the excavator generated by the drilling disrupts the crosstalk with the expansion piece 3 attached to the drill bit 2, and presses the disturbed cutting outward with the curved blade surface of the expansion piece 3. Furthermore, as the auger shaft 1 descends, the excavator tries to move up around the auger shaft 1, but due to the rotation of the auger shaft 1, the excavator collapses the hole at the apex circumference 1'' of the auger shaft 1. It is expanded by the surrounding wall A, and this forms a solid wall B on the surrounding wall of the hole.As described above, the ground drilling device according to the present invention is expanded by the expansion piece 3 at the tip of the drill bit. At the same time as digging into the ground, the auger tip excavator was mixed and disturbed while expanding outward for three more times: Square auger 1
．． The 1' key has very small excavation resistance, but there is no risk of collapse by expanding and compacting the excavator on the circumferential wall of the hole with a circumference of 1'' at the apex angle. The significance lies in the fact that a robust hole surrounding wall can be created extremely reliably and with a simple device.

'Although the auger koji PI is described as having a triangular shape, the shape of the auger shaft 1 is not limited to this shape, but in view of the hardness and weakness of the excavated ground, the wall of the construction hole, etc., the shape of the auger shaft 1 is square. , a polygonal shape such as a hexagonal shape, an ellipse, a perfect circular shape, or any other shape may be selected and used.

Furthermore, by filling a consolidating material such as mortar from the tip injection port 5 in the same direction as the digging hole construction work, it is possible to easily construct a mortar column in the ground that can be well stirred and kneaded with the gunwale piece 3. I can do it.

Brief Explanation of the Drawings The drawings illustrate embodiments of the ground drilling apparatus according to the present invention, and Figure 1 is a side view; FIG. 2 is a bottom view, FIG. 3 is a cross-sectional view, and FIG. 4 is a diagram of the construction of the false hole.

Explanation of symbols, 1... Force - is the axis, 2... Drill tip metal fitting, 3.
・・・・Gender opening piece, 4・・・・・・ Sakibori blade, 5……
Injection port, 6...Flow pipe, ``7...Driver,
a... Auger rotation diameter, b... Expansion piece rotation locus, A... excavation hole, B... consolidation wall.

Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. A conical tip portion is provided at the tip of the auger shaft, which has a substantially triangular cross section with each cylindrical surface portion curved and concave inward of the tree to form a pressed earth surface, and each apex edge of the conical tip portion is connected to the base. In the non-rotating direction, the cutting edge length is the diameter of the treetop than the rotational circumference of the auger outer diameter.
A ground drilling device characterized in that it is equipped with an expanding piece whose blade surface is bent in the axial direction to form a compacted earth surface.